Cloud Storage Gateway:Why are write operations to gateways slow?

Reason

Description

Solution

Throttled cache disk

Throttling is triggered if the amount of data that is simultaneously written into the cache disk is greater than 80% of the total data cache size.

1. Troubleshoot problematic data uploads that cause failures in releasing cache space. The following factors cause problematic uploads:

   • You attempt to upload data to a bucket that does not exist.

   • The bucket policy denies access from the gateway.

   • The share is mapped to an Archive bucket or a Cold Archive bucket.

   • The size of files that are being simultaneously written to the cache disk exceeds the size of available data cache. As a result, the files cannot be closed and uploaded within the expected period of time.

2. Decrease the amount of data that can be simultaneously written to the cache disk.

3. Increase the cache capacity of the share. For more information, see Increase cache disk capacity.

Single-threaded data writes or inadequate concurrency

Single-threaded writes or an insufficient number of concurrent writes may cause low write efficiency.

If your application supports concurrency, we recommend that you increase the number of concurrent writes to improve write efficiency. For example, File Explorer on Windows perform single-threaded writes. However, you can use tools such as robocopy to improve write efficiency on Windows.

Frequent small I/O operations

In small I/O scenarios, frequent writes of small data, such as 4 KB, cause reduced write efficiency.

Combine small I/O operations into larger ones to enhance write efficiency.

Too many files in the folder

Writing a large number of files (such as hundreds of thousands) in the same directory may lead to directory locking, which in turn can affect write performance.

Distribute files across multiple directories for writing in order to reduce directory lock contention within the same directory.

Disk I/O performance

Inadequate disk read/write speeds can negatively impact write performance.

Using cache disks that provide better I/O performance, such as Enterprise SSDs.